Abstract: A electromechanical buzzer provides a rotational volume control having a flange extending over the armature of the buzzer with a downwardly extending wedge surface reducing the vibrational range of the armature. The wedge surface is oversized so that when the armature is compressed against its associated electromagnet coil, the armature may move upward against a spring to complete its rotational travel without binding. Detent and stops on the rotational operator shaft are constructed to permit assembly of the operator shaft to the cover without interference between the parts of the detent and stop divided between the cover and the rotational operator shaft and then to permit a rotation of the operator shaft to engage the stops and detent components in a second angular range and constrain rotation to that second angular range thereafter. Assembly of the detent components reduces play in the detent such as might permit movement of the rotational operator shaft under the vibration caused by the buzzer.